Non-vented vial drug delivery

ABSTRACT

This disclosure relates to fluid line sets and related methods. In certain aspects, the fluid line sets include a vial adapter connected to a first end of a fluid line, and a cap removably attached to a second end of the fluid line such that the cap seals the second end of the fluid line. The vial adapter includes a base, a spike extending from a central region of the base, and a sidewall extending from the base and substantially surrounding the spike. The base and the side wall at least partially define a cavity configured to receive a portion of a vial. The cap includes a deformable portion at least partially defining a gas chamber, and the cap is configured so that deformation of the deformable portion causes gas to be forced from the gas chamber to the vial adapter via the fluid line.

CROSS REFERENCE RELATED APPLICATION

This application is divisional application of and claims priority toU.S. application Ser. No. 14/744,304, filed on Jun. 19, 2015.

TECHNICAL FIELD

This disclosure relates to non-vented drug delivery.

BACKGROUND

During hemodialysis, impurities and toxins are removed from the blood ofa patient by drawing the blood out of the patient through a blood accesssite, typically via a catheter, and then passing the blood through anartificial kidney (often referred to as a “dialyzer”). The artificialkidney includes microtubes that each separate a first conduit from asecond conduit. Generally, a dialysis solution (often referred to as a“dialysate”) flows through the first conduit of the dialyzer while thepatient's blood flows through the second conduits of the dialyzer,causing impurities and toxins to be transferred from the blood to thedialysate through the microtubes. The impurities and toxins can, forexample, be removed from the blood by a diffusion process. After passingthrough the dialyzer, the purified blood is then returned to thepatient.

When kidney failure is diagnosed, patients are typically givenmedication to help control the symptoms and slow the progress of damageto the kidneys. Patients with chronic kidney failure generally takedrugs, such as iron supplements, to control the balance of minerals inthe body.

SUMMARY

In one aspect of the invention, a fluid line set includes a vial adapterhaving a base, a spike extending from a central region of the base, asidewall extending from the base and substantially surrounding thespike, a fluid line having a first end connected to the vial adapter anda second end, and a cap removably attached to the second end of thefluid line such that the cap seals the second end of the fluid line. Thebase and the side wall at least partially define a cavity configured toreceive a portion of a vial. The cap includes a deformable portion thatat least partially defines a gas chamber. The cap is configured so thatdeformation of the deformable portion causes gas to be forced from thegas chamber to the vial adapter via the fluid line.

In another aspect of the invention, a method includes causing gas toflow through a fluid line of a dialysis system until the gas enters adrug vial connected to a vial adapter assembly causing a pressure withinthe drug vial to increase, and clamping the fluid line after increasingthe drug vial pressure.

In yet another aspect of the invention, a dialysis system includes adialysis machine including a blood pump and a drug pump, a blood lineset including a blood line that can be operably connected to the bloodpump and a drip chamber in fluid communication with the blood line, afluid line set including a fluid line including a first end connected toa vial adapter and a second end, and a cap removably attached to thesecond end of fluid line such that the cap seals the second end of thefluid line. The cap includes a deformable portion at least partiallydefining a gas chamber. The cap is configured so that deformation of thedeformable portion causes gas to be forced from the gas chamber to thevial adapter via the fluid line.

Implementations can include one or more of the following features.

In some implementations, the cap further includes a one-way valve.

In certain implementations, the one way valve is disposed between thesecond end of the fluid line and the gas chamber to prevent fluid frompassing into the gas chamber from the fluid line.

In some implementations, the chamber includes a volume of sterile gas.

In certain implementations, the sterile gas is air.

In some implementations, the volume of sterile gas includes less than 2ml of sterile gas.

In certain implementations, the volume of sterile gas includes 1 to 2 mlof sterile gas.

In some implementations, the fluid line includes a first end connectedto the vial adapter and a second end and a cap removably attached to thesecond end of fluid line such that the cap seals the second end of thefluid line. The cap includes a deformable portion at least partiallydefining a gas chamber. The cap is configured so that deformation of thedeformable portion causes gas to be forced from the gas chamber to thevial adapter via the fluid line.

In certain implementations, the method includes fluidly connecting adrug vial with the fluid line via the vial adapter assembly. The vialadapter assembly includes a vial adapter having a spike extending from acentral region of a base.

In some implementations, the drug vial includes an initial internalpressure equal to an ambient pressure.

In certain implementations, the drug vial includes an initial gas volumeof 0.3 ml to 2 ml.

In some implementations, the gas flowing through the delivery lineintroduces gas into the drug vial.

In certain implementations, the gas volume within the drug vial is 2 mlto 3 ml.

In some implementations, the introduced gas within the drug vialincreases a pressure within the drug vial.

In certain implementations, the method further includes removing the capfrom the second end of the fluid line.

In some implementations, the method further includes connecting thesecond end of the fluid line to an extracorporeal blood circuit.

In some implementations, the method further includes delivering drugfrom the drug vial to the extracorporeal blood circuit via the drugdelivery line.

In certain implementations, the cap further includes a one-way valve.

In some implementations, the one-way valve is disposed between thesecond end of the fluid line and the gas chamber to prevent fluid frompassing into the gas chamber from the fluid line.

In certain implementations, the chamber includes a volume of sterilegas.

In some implementations, the sterile gas is air.

In certain implementations, the volume of sterile gas includes less than2 ml of sterile gas.

In some implementations, the volume of sterile gas includes 1 to 2 ml ofsterile gas.

In some implementations, the dialysis system further includes a drugvial connected to the vial adapter, such that deformation of thedeformable portion introduces causes gas to be forced into the drugvial.

In certain implementations, the drug vial includes an initial gas volumeof 0.3 to 2 ml.

In some implementations, the additional gas increases the gas volume to1 to 3 ml.

Implementations can include one or more of the following advantages.

The drug line sets described herein are designed to be used in medicalsystems, such as hemodialysis systems. Introducing air into the drugvials via the drug line sets of such systems decreases the vacuumpressure within the drug vial, which helps to ensure that the vacuumpressure generated within the drug line set by a pump exceeds thecompeting vacuum within the drug vial. This additional air improves theprocess of priming the system by helping to ensure that the desiredamount of drug can be withdrawn from the drug vial. In addition,introducing additional air into the drug vial can account for air volumevariations between drug vials of different manufacturers ormanufacturing lots, which helps to expand the compatibility of themedical devices with a variety of drug vials without modifying anyhardware components. Further, by introducing air into the drug vial viathe drug delivery line set, both the drug delivery line and theadditional air can be sterilized using a single sterilization process.

Other aspects, features, and advantages will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a front view of a hemodialysis machine including a drugdelivery module mounted in a mid-section of the machine.

FIG. 2 is an enlarged view of the midsection of the hemodialysis machineof FIG. 1.

FIG. 3 is a perspective view of a drug delivery fluid line set includinga vial spiking assembly and priming cap connected to a drug deliveryline.

FIG. 4A is a perspective view of the drug delivery line set includingthe priming cap in the unactuated state and an enlarged view of thepriming cap in an unactuated state.

FIG. 4B is a perspective view of the drug delivery line set includingthe priming cap in the actuated state and an enlarged view of thepriming cap in an actuated state.

FIG. 5 is an enlarged view of the drug delivery module of thehemodialysis machine of FIG. 1 isolated from the hemodialysis machine.

FIG. 6 is a perspective view of the vial spiking assembly and a spikecover.

FIG. 7 is a perspective view of the drug delivery line set partiallyloaded into the drug delivery module.

FIG. 8 is a perspective view of the drug vial being loaded onto the vialadapter.

FIG. 9 is a perspective view of the drug delivery line set being loadedinto a peristaltic pump of the drug delivery module.

FIG. 10 is an enlarged view of the midsection of the hemodialysismachine of FIG. 1 showing the drug delivery line set connected to thehemodialysis set prior to operating the pumps. Certain details of thehemodialysis machine have been omitted for simplicity.

FIGS. 11A and 11B are a perspective views of an alternative priming capin the form of a dropper.

DETAILED DESCRIPTION

Referring to FIG. 1, a hemodialysis system 100 includes a hemodialysismachine 102 having a drug delivery module 104 to which a drug deliveryline set 106 is connected. The drug delivery module 104 and the drugdelivery line set 106 can be used to deliver one or more drugs to apatient during hemodialysis treatment. Specifically, the drug can bedelivered from a drug vial 108 through the drug delivery line set 106 toa drip chamber 110 of a blood line set 112 where the drug mixes withblood before the blood is returned to the patient. As will be describedin detail below, a priming cap 116 (shown in FIGS. 3, 4A, 4B, 5, and 11Aand 11B) of the drug delivery line set 106 includes a diaphragm that canintroduce air into the drug vial 108 using a drug delivery line 140 ofthe drug delivery line set 106. Introducing air into the drug vial 108modifies the internal pressure within the drug vial 108 to ensure thatthe vacuum pressure within the drug delivery line 140, throughouttreatment, exceeds the competing vacuum within the drug vial 108.

Still referring to FIG. 1, the hemodialysis machine 102 includes adisplay 118 and a control panel 120, whereby the user selections andinstructions can be sent to, and stored by, a control unit of thehemodialysis machine 102. The hemodialysis machine 102 also includesmodules that house components used to perform hemodialysis, includingthe drug delivery module 104, a blood pump module 122, and a leveldetector module 124.

In use, the disposable blood line set 112, which forms a blood circuitwith the patient, is connected to the modules 104, 122, and 124 on thefront side of the hemodialysis machine 102. During treatment, patientlines 126, 128 of the blood line set 112 are connected to the patient,and a pump tubing segment 130 of the blood line set 112 is connected toa blood pump 132 of the blood pump module 122. As the blood pump 132 isoperated, blood is drawn from the patient, pumped through a dialyzer 134and the drip chamber 110 of the blood line set 112, and then returned tothe patient.

FIG. 2 illustrates the mid-section of the hemodialysis machine 102 withthe blood line set 112 and the drug delivery line set 106 connected tothe modules 104, 122, and 124 and with the drug vial 108 inserted into avial adapter 136 of the drug delivery line set 106. The blood line set112 includes the pump tubing segment 130, which is connected to theblood pump module 122 in a manner so as to operatively engage the bloodpump 132 of the blood pump module 122. Operation of the blood pump 132pumps blood through the blood line set 112.

Still referring to FIG. 2, the drip chamber 110 of the blood line set112 is positioned at a location downstream from the blood pump 132. Thedrip chamber 110 permits gas, such as air, in the blood to escape fromthe blood before the blood is returned to a patient. The drip chamber110 can be secured to the level detector module 124 so as to align witha fluid level detector 138 that is adapted to detect the level of liquid(e.g., blood and/or saline) within the drip chamber 110. The drugdelivery line 140 of the drug delivery line set 106 is connected to theblood line set 112 at a location between the dialyzer 134 and the dripchamber 110 via a luer lock connector 142 disposed on the drug deliveryline 140. Specifically, the luer lock connector 142 is connected to amating luer locking fitting on a level adjust line 144 that is connectedto the top of the drip chamber 110. A clamp 147 is attached to the leveladjust line 144 and is used to permit or block fluid from passingbetween the drug delivery line set 106 and the blood line set 112.

The drug delivery line set 106 includes the drug delivery line 140,which is connected to the drug delivery module 104 in a manner so as tooperatively engage the drug pump 150 of the drug delivery module 104.When the drug pump 150 is being operated, a vacuum pressure (e.g., up toabout −12 psi) is applied to the drug vial 108 that is connected to thedrug delivery line 140. In certain cases, the initial pressure in thedrug vial 108 can vary slightly from above to below ambient pressure dueto variations in conditions during manufacturing. The initial air volumewithin the drug vial 108 is generally 2 ml of air or less (e.g., fromabout 0.40 ml to 1.75 ml of air) due to drug vial arrangements (e.g.,total interior volume, ambient pressure during vial filling, and stoppervolume), and when all of the drug has been delivered, the endingpressure within the vial is −15 psi or less (e.g., −7 to −15 psi). Asthe quantity of drug in the drug vial decreases, a vacuum (or negativepressure) within the drug vial increases because the drug vial 108 isnot vented. In other words, the pressure within the drug vial 108progresses from 14.7 psi toward −15 psi (e.g., −7, −7.22, −8, −13, −13.6psi) as the drug is being delivered. In certain cases, the vacuumgenerated in the drug delivery line 140 exceeds the vacuum within thedrug vial 108. As a result, the drug is drawn from the drug vial 108through the drug delivery line 140. However, when the pump 150 is unableto generate a vacuum in the drug delivery line 140 that exceeds thevacuum in the drug vial, the pump 150 can no longer draw drug from thedrug vial 108 into the drug delivery line 140. Thus, any remaining drugwithin the drug vial 108 is not delivered to the patient. The remainingdrug can result in under-delivery of a drug to the patient and/or limitthe amount of available drug per drug vial.

As shown in FIG. 3, the drug delivery line set 106 includes the vialadapter 136 to which the drug delivery line 140 is attached. The drugdelivery line set 106 also includes a priming cap 116 that is removablyattached to the drug delivery line 140. The drug delivery line 140 andthe priming cap 116 include sterile air. The priming cap 116 includes abistable diaphragm 156, which defines a top boundary of an internalchamber 151. The air volume can be selected such that, upon activationof the priming cap 116, the bistable diaphragm 156 displaces asufficient air volume into a drug vial (e.g., the drug vial 108) toenable a pump (e.g., the drug pump 150) to deliver the desired dosage orsubstantially all of the drug (e.g., 100%, at least 95%, at least 90%,or at least 80%) within the drug vial based on the capabilities of thepump. For example, the internal chamber 151 can be sized and shaped tostore an air volume of about 3 ml or less (e.g., 0.5 ml or less, 1 ml orless, 1.5 ml or less, or 2 ml or less), which can be delivered into adrug vial (e.g., the drug vial 108) through the drug delivery line 140when the priming cap 116 is activated.

In addition to the priming cap 116, the drug delivery line set 106 caninclude a spike cover 154 is removably secured to the vial adapter 136by an interference fit. The spike cover 154 can be made of a moldablematerial, e.g. polyethylene. The spike cover 154 is removed from thevial adapter 136 prior to use to allow a drug vial (e.g., the drug vial108) to be inserted into the vial adapter 136.

FIGS. 4A and 4B illustrate the drug delivery line set 106 with the drugvial 108 inserted into the vial adapter 136. The bistable diaphragm 156is movable between a first position in which the bistable diaphragm 156assumes a convex shape (as shown in FIG. 4A) and a second position inwhich the bistable diaphragm assumes a concave shape (as shown in FIG.4B). For example, the bistable diaphragm 156 is convex prior to beingdepressed in the direction shown by an arrow 141 and is concave afterthe priming cap 116 is depressed. Activation of the priming cap 116 isachieved by depressing the convex surface to create a concave surface.

The priming cap 116 can be made from a plastic material (e.g. highdensity Polyethylene (HDPE), polyethylene, polyvinylchloride, polyamide,or a blend of moldable plastics). The bistable diaphragm 156 can beeconomically produced using an injection molding technique, for example.The priming cap 116 removably attaches to the drug line 140 using a luerconnection to form an air-tight seal with the fluid line 140. Otherair-tight connection mechanisms may also be used (an interference fit).

The drug delivery line set 106 also includes a one-way valve 145 (e.g.,a check valve) between the luer lock connector 142 of the drug deliveryline set 106 and the drug vial 108. The one-way valve 145 permitsdelivery of air from the internal chamber 151 to the drug vial 108, butprevents air from re-entering the priming cap 116 when the bistablediaphragm 156 is deformed and/or released. The one-way valve 145 may bea duckbill valve, an umbrella valve, a ball-check valve, diaphragm checkvalve, swing check valve, stop-check valve, lift-check valve or acombination thereof.

As drug is delivered from the drug vial 108, any remaining air withinthe drug vial 108 expands and a vacuum pressure within the drug vial 108increases. The final pressure within the drug vial can be determinedwith the following equations:P _(atm)(V _(initial air))=P _(vial)(V _(min. air))  Equation 1 MinimumFinal Vial PressureP _(atm)(V _(initial air))=P _(vial)(V _(max. air))  Equation 2 MaximumFinal Vial Pressure

where

P_(atm) is atmospheric pressure.

V_(initial air) is the initial volume of air inside the vial;

P_(vial) is the final pressure within the vial; and

V_(max) is maximum volume of air inside the vial.

By subtracting the pressure within the drug delivery line 140 (e.g.,ambient pressure or 14.7 psi) from the calculated final vial pressure,the pumping capability necessary to evacuate all drug can be determined.The initial volume of air inside the vial can be adjusted such that pump(e.g., the drug pump 150) can generate a vacuum (based on thecapabilities of the pump) in the drug line that exceeds final vacuumwithin the drug vial in view of the maximum and minimum conditions givenarrangement of a drug vial (e.g., the total vial volume, the air volume,the drug volume, and the stopper volume). This adjustment helps toensure that the medical systems described herein remain compatible witha variety of drug vial designs and/or manufacturing deviations withoutreplacing or upgrading system components (e.g., pumps).

FIG. 5 shows the drug delivery line set 106 connected to the drugdelivery module 104 prior to connecting the drug delivery line 140 tothe blood line set 112. As shown, the end of the drug delivery line 140is connected to a storage clip 148 of the drug delivery module 104. Thedrug delivery line 140 passes through a peristaltic drug pump 150. Priorto use, a user will prime the drug vial 108 with air by depressing thepriming cap 116, which will be explained in further detail later. A userthen would unclip the drug delivery line 140 from the storage clip 148and connect it to the blood line set 112 in the manner shown in FIGS. 1and 2.

Still referring to FIG. 5, the drug delivery module 104 includes a fluidflow detector 152. The fluid flow detector 152 is capable of detectingair bubbles within the drug delivery line 140. As a result, the fluidflow detector 152 can determine whether the drug vial 108 is empty. Insome implementations, the fluid flow detector 152 is an opticaldetector. The OPB 350 level detector made by Optek® can, for example, beused. Other types of optical detectors can alternatively or additionallybe used. Similarly, other types of sensors, such as sensors utilizingultrasound technology can be used as the fluid flow detector. Examplesof such sensors include the AD8/AD9 Integral Ultrasonic Air-In-Line, AirBubble Detector and the BD8/BD9 Integral Ultrasonic Air Bubble,Air-In-Line & Liquid Level Detection Sensors (manufactured by Introtek®International (Edgewood, N.Y.)). In some implementations, the fluid flowdetector 152 includes a sensor that, in addition to sensing the presenceof an air bubble within its associated drug delivery line 140, can sensethe presence of the drug delivery line 140 itself.

Still referring to FIG. 5, the drug delivery line 140 passes through(e.g., is threaded through) the peristaltic drug pump 150. Theperistaltic drug pump 150 works by compressing the drug delivery line140 and moving a “pillow” of fluid that is pinched between two points ofthe drug delivery line 140 by the pump rollers. Each “pillow” of fluidis of a volume determined by the roller spacing and the inside diameterof the drug delivery line 140. When the peristaltic drug pump 150operates at a given speed, a series of these “pillow” shaped volumes offluid are delivered to the drip chamber 110. The rate of fluid deliverycan be changed by altering the speed of the peristaltic drug pump 150.The pump speed can be controlled, for example, by adjusting the voltagedelivered to the peristaltic drug pump 150. The voltage delivered to themotor of the peristaltic drug pump 150 can, for example, be adjusted bythe control unit (e.g., software of the control unit) until the correctspeed (e.g., the speed that corresponds to the desired flow rate) ismeasured by an encoder of the peristaltic drug pump 150.

During use, the drug delivery line set 106 is fluidly connected to theblood line set 112 of the hemodialysis system 100, as shown in FIGS. 1and 2. Drugs are delivered to the drip chamber 110 using the drugdelivery module 104. The drugs mix with the patient's blood within thedrip chamber 110 and are then delivered to the patient along with thepatient's filtered blood.

FIG. 6 illustrates the vial adapter assembly with the spike cover 154removed from the vial adapter 136. The vial adapter 136 includescircumferentially spaced side wall segments 157 that extend upwardlyfrom a base 155 to form a receiving cavity 159 sized and shaped toreceive a drug vial. A spike 164 extends from a central region of thebase 155 and is sized and shaped to pierce a seal of the drug vial whenthe drug vial is inserted into the receiving cavity 159. The spike 164has a central passage in fluid communication with a cavity 163 of thespike cover 154 when the spike cover 154 is positioned over the spike164.

As shown in FIG. 6, the circumferential side wall segments 157 of thevial adapter 136 extend to a slightly greater height than the spike 164of the vial adapter 136. Adjacent side wall segments 157 are spacedapart by longitudinal/vertical slots 153. The side wall segments 157together with the base 155 form the receiving cavity 159 that isconfigured to receive a portion of a drug vial (e.g., a collar of a drugvial cap assembly). In some implementations, the receiving cavity 159 isconfigured to receive a collar having a diameter that is about 0.75inches to about 1 inch (e.g., about 0.875 inches.) The side wallsegments 157 are configured to deflect away from the longitudinal axisof the vial adapter 136 when a radially outward force is applied (e.g.,as a result of the drug vial being inserted into the receiving cavity159) and rebound towards the longitudinal axis when the force isreleased.

Still referring to FIG. 6, protrusions 161 on side wall segments 157 ofthe vial adapter 136 help secure a vial within the receiving cavity 159of the vial adapter 136. The extension of the side wall segments 157 toa slightly greater height that the spike 164 of the vial adapter 136also help to ensure that the spike 164 is not inadvertently contacted(e.g., by the user) prior to loading of the drug vial 108 onto the spike164. This can, for example, help to prevent the spike 164 from becomingcontaminated before it is inserted into the drug vial.

In some implementations, the spike 164 is formed of one or more medicalgrade plastics, such as PVC or acrylonitrile butadiene styrene (ABS).However, other medical grade plastics can be used to form the spike 164.Similarly, certain metals, such as stainless steel, could be used toform the spike 164.

Another feature of the vial adapter assembly that prevents inadvertentcontact and contamination is the spike cover 154. The spike cover 154 isplaced into the receiving cavity 159 of the vial adapter 136 to coverthe spike 164. The spike cover 154 can help prevent objects fromcontacting and contaminating the spike 164 prior to use and can alsoprevent users from inadvertently sticking themselves with the spike 164.The spike cover 154 is configured to be received in the receiving cavity159 and temporarily retained by the side wall segments 157. For example,the spike cover 154 can be retained via a loose interference fit. Theside wall segments 157 provide a resisting force of about 0.75 lbf toabout 2 lbf to retain the spike cover 154 when it is retained by thevial adapter 136.

Prior to hemodialysis, the user connects the drug delivery line set 106,which includes the vial adapter 136, the spike cover 154, and the drugdelivery line 140, to the drug delivery module 104 of the hemodialysismachine 102. The drug delivery line set 106 is typically provided to theuser in a sterile bag with the priming cap 116 connected to the end ofthe drug delivery line 140 opposite the vial adapter 136. To connect thedrug delivery line set 106 to the drug delivery module 104, the userfirst opens the sterile bag and removes the drug delivery line set 106.

Referring to FIG. 7, the user then opens a door 158 of the fluid flowdetector 152, places the vial adapter assembly (e.g., the vial adapter136 and spike cover 154) into a vial holder 160, and threads the drugdelivery line 140 through a bubble detector 162 of the fluid flowdetector 152. The user also opens a door 166 of the peristaltic drugpump 150 and threads the drug delivery line 140 through the peristalticdrug pump 150. The door 166 typically remains open so that the drugdelivery line 140 is not crimped between the door 166 and the rollers ofthe peristaltic drug pump 150. This permits both fluid and air to flowfreely through the drug delivery line 140.

Referring to FIG. 8, the drug vial 108 is placed on the vial adapter 136so that a spike 164 pierces a seal of the drug vial 108 and places thevial in fluid connection with the drug delivery line set 106 (e.g., asshown in FIGS. 1 and 2). When placed on the vial adapter 136, the sealand the spike 164 form a fluid- and air-tight seal. A user thendepresses and/or deforms the priming cap 116 (as shown in FIG. 4B) todeliver air into the drug vial 108.

Referring to FIG. 9, the user then closes the door 166 of theperistaltic drug pump 150 and the door 158 of the fluid flow detector152, engaging the peristaltic drug pump 150 and the fluid flow detector152 with the drug delivery line 140. As discussed above, the drugdelivery line 140 is crimped within the door 166. This arrangement helpsto retain the modified drug vial pressure and/or the additional airwhen, for example, a priming cap is removed and/or the drug line isfluidly connected to another line because portions of the drug line 140downstream from the door 166 may equalize with another pressure, e.g.,with the pressure within the blood line set.

Referring to FIG. 10, the drug delivery line 140 is then connected tothe drip chamber 110 using an aseptic technique. As discussed above,this typically involves removing the priming cap 116 and connecting theluer lock connector 142 on the end of the drug delivery line 140 to amating luer lock fitting on the level adjust line 144 extending from thedrip chamber 110. In addition, a priming fluid bag 168 is connected tothe blood line set 112 via a priming fluid line 169. The priming fluidbag 168 is connected to the priming fluid line 169 by a luer lockconnection. The priming fluid line 169 also includes clamps 171 and 172that are used to regulate the fluid flow from the priming fluid bag 168to the blood line set 112. The patient lines 126 and 128 are connectedto each other via a luer connector 173 at this point to allow primingfluid to circulate through the blood circuit.

Still referring to FIG. 10, after the drug delivery line set 106 hasbeen connected to the drip chamber 110, which is attached to the leveldetector module 124, the peristaltic drug pump 150 is then operated todeliver drug to the drip chamber 110 of the blood line set 112. Forexample, the system can undergo a priming process in which the drug pump150 causes a portion of the drug to be drawn from the drug vial 108until the drug is detected by the bubble detector 162. The blood pump132 is also operated to cycle priming fluid through the blood line set112 and through the dialyzer 134. Air within the blood circuit and drugdelivery line can collect in the drip chamber 110 and then be removedfrom the system prior to treatment.

After priming is complete, the priming fluid line 169 is disconnectedfrom the blood circuit or clamped, and the patient lines 126 and 128 aredisconnected from each other and connected to the patient to allow thepatient's blood to circulate through the blood circuit. Duringtreatment, the peristaltic blood pump 132 is operated to pull blood fromthe patient via the arterial patient line 126, run the blood through theblood circuit, and then return the blood to the patient via the venouspatient line 128. The drug pump 150 is operated to deliver drug from thedrug vial 108 to the drip chamber 110 through the drug delivery line140. The drug can mix with the blood in the drip chamber 110 beforeflowing to the patient.

As discussed above, the drip chamber 110 of the hemodialysis system 100functions as an air trap. Thus, any gases (e.g., air) introduced intothe system are able to escape from the drug and blood within the dripchamber 110 before the mixture of blood and drug is delivered to thepatient. In addition to removing air from the system, the drip chamber110 provides other benefits. For example, the drip chamber 110 providesvisual confirmation of drug delivery and allows the delivered drug tomix with the patient's blood prior to reaching the patient. In addition,the drip chamber 110 allows for simple luer connection to the drugdelivery line set 106. As a result, the patient need not be stuck withan additional needle in order to receive the drug from the drug vial108.

While certain embodiments have been described, other embodiments arepossible.

While the priming cap 116 has generally been shown and described asmonolithic, the priming cap 116 can be a composite structure where thebistable diaphragm 156 is an attachable component that could be adifferent material from the main body of the priming cap. The bistablediaphragm 156 can be attached to the main body of the priming cap withany attachment known in the art, such as adhesives, fasteners, orwelding.

Referring to FIGS. 11A and 11B, while the priming cap 116 has beengenerally shown as having an asymmetric body partially defined by thebistable diaphragm 156, the priming cap 116 can alternatively oradditionally have a uniform compressible body such that any portion ofthe priming cap can be compressed to introduce air to the drug vial 108.For example, the priming cap can include a compressible body portion 177(e.g., a bulbous portion) surrounding an internal gas chamber 178 influid communication (e.g., via an internal passage) with an integralneck portion 175 extending from the compressible body portion 177. Thecompressible body portion 177 can alternatively or additionally have auniform shape. For example, the compressible body portion 177 can bearranged as an elliptical cylinder with at least one spherical end (asshown in FIG. 11A) or as a cylinder with at least one spherical end (asshown in FIG. 11B). The integral neck portion 175 can include afluid-tight (e.g., air-tight) connection (as described with above) toremovably connect the priming cap 116 to the fluid line. Compressing thebody portion 177 can deform a portion of the deformable wall structure180, thereby reducing the volume of the internal gas chamber 178 andexpelling at least a portion of gas (e.g., air and/or sterile air) fromthe interior gas chamber 1758. The deformable wall structure 180 definesat least a top surface and a bottom surface of the internal gas chamber178. This arrangement provides multiple surfaces for a user to deformand/or compress to deliver gas to the drug vial 108 via the drug line140.

While the diaphragm has been described as being bistable, in someembodiments, it can have a single stable state. The user continuouslydepresses the diaphragm in order to maintain the additional airdisplaced into the drug vial. The user can control the amount of airdelivered based on the amount of pressure the user places on thediaphragm. The user can connect the drug delivery line set to the dripchamber while depressing the diaphragm.

While the priming cap 116 has generally been shown to include a oneway-valve, in some embodiments, the priming cap can additionally oralternatively be arranged to occlude the drug delivery line 140 viadepression of the bistable diaphragm 156, thereby preventing air fromre-entering the priming cap 116. Upon depression and/or deformation, thebistable diaphragm 156 can contact an opposing wall surface to form afluid-tight seal until the cap is removed.

While a luer lock connection has been described as being used to fluidlyconnect the drug delivery line set with the priming cap 116 and the dripchamber, any of various other types of fluid connections can beimplemented, such as an interference fit, tab connection, or temporaryadhesive.

While during priming the drug vial the drug delivery line is generallyshown as threaded through the peristaltic drug pump, the drug deliveryline may remain outside of the peristaltic pump before the priming cap116 is removed. For example, a user can deform or depress the primingcap 116 before threading the drug delivery line through the peristalticdrug pump (e.g., over the pump rollers).

While the hemodialysis machine has generally been shown to includemodules used to perform hemodialysis, including the drug deliverymodule, the blood pump module, and the level detector module, othermodules may also be included. For example, a heparin pump module mayalso be included. The heparin pump module can include a heparin pumpthat receives a syringe connected to a drug delivery line that isconnected to the blood line at a location between the blood pump. Thesyringe pump can be operated to move a plunger of the syringe and thuseject liquid from the syringe through the drug delivery line. Theheparin pump module can thus be used to inject heparin from the syringeinto the blood circuit via the drug delivery line during a hemodialysistreatment.

While the drug delivery devices have been described as being used withhemodialysis systems, the devices, assemblies, and methods describedherein can be used with various other types of drug delivery processesand systems. For example, in some implementations, the drug vial spikingdevices are used for delivering drugs during peritoneal dialysistreatments, blood perfusion treatments, intravenous infusion treatments,or other medical fluid handling treatments, such as delivering drugsintravenously.

A number of implementations have been described. Nevertheless, it willbe understood that various modifications may be made without departingfrom the spirit and scope of the description. Accordingly, otherimplementations are within the scope of the following claims.

What is claimed is:
 1. A method comprising: causing a gas to flow through a fluid line of a dialysis system until the gas enters a drug vial connected to a vial adapter assembly causing a pressure within the drug vial to increase; and clamping the fluid line after increasing the drug vial pressure, wherein the fluid line comprises a first end connected to the vial adapter assembly and a second end, and a cap removably attached to the second end of fluid line such that the cap seals the second end of the fluid line, the cap comprising: a deformable portion at least partially defining a gas chamber, the deformable portion being a bistable diaphragm configured to be activated by depression so that deformation of the deformable portion causes gas to be forced from the gas chamber to the vial adapter assembly via the fluid line.
 2. The method of claim 1, further comprising fluidly connecting a drug vial with the fluid line via the vial adapter assembly, the vial adapter assembly comprising a vial adapter having a spike extending from a central region of a base.
 3. The method of claim 2, wherein the drug vial includes an initial internal pressure equal to an ambient pressure.
 4. The method of claim 3, wherein the drug vial includes an initial gas volume of 0.3 ml to 2 ml.
 5. The method of claim 2, wherein the gas flowing through a delivery line introduces gas into the drug vial.
 6. The method of claim 5, wherein the introduced gas volume within the drug vial is 1 ml to 2 ml.
 7. The method of claim 5, wherein the introduced gas within the drug vial increases a pressure within the drug vial.
 8. The method of claim 1, further comprising removing the cap from the second end of the fluid line.
 9. The method of claim 8, further comprising connecting the second end of the fluid line to an extracorporeal blood circuit.
 10. The method of claim 9, further comprising delivering drug from the drug vial to the extracorporeal blood circuit via a drug delivery line. 